Sure am glad I'm down here where I can purchase 10, 30, 30 ampere 20% boosters without need od a Dun & Bradstreet. My little 20-amp unit is half the size of a shoe box and it was designed to aid starting of well motors. A 20% boost brings 100 vac right back to 120. Automatic switching. Cost? About 112 US Dollars. My 20K joule MOV and 10, 000 ampere TVS suppression boxes go everywhere I go. 2 10 gauge wires with 400 volt MOVs set radially around them. The TVS are rated at 190 volts peak-to-peak.